OpenStudy (anonymous):

Which of the following is a subset of the set A: {adults between the ages of 21 and 35} {adults between the ages of 23 and 30} {an adult 40 years old} {adults under 21} {adults over 35}

OpenStudy (anonymous):

{adults between the ages of 23 and 30}

OpenStudy (anonymous):

{adults between the ages of 23 and 30}

OpenStudy (anonymous):

Visualize it as a circle with that label. The category is another circle that fits within that bigger circle.